1. Field of the Invention
The invention relates to a brush block and a slip-ring assembly for transferring electrical signals by sliding contacts between parts rotatable against each other. On a sliding track of electrically conductive material, at least one sliding contact also referred to as a brush, also of an electrically conductive material, slides. The galvanic contact between the sliding tracks and the brush enables the transfer of electrical power.
2. Description of Relevant Art
DE 10 2008 001 361 A1 discloses a slip-ring assembly where a brush with at least two sliding wires runs in a sliding track with a V-groove. The sliding wires have different diameters and contact the sliding track at different angular positions. This leads to increased tolerance against mechanical vibrations and impact and reduced contact resistance.
EP 0662736 A discloses a slip-ring assembly, where a single brush has several wires that run in a V-groove. This leads to a lower contact resistance due to connecting several contacts in parallel.
U.S. Pat. No. 4,398,113 A discloses another slip-ring assembly with brushes having a plurality of finest wires. Again, the multiple contacts lead to a relatively low contact resistance.
None of these slip ring assemblies allows for a reliable electrical contact at high shock and impact loads. During short time, strong external impact or vibrations, short-term contact interruptions occur from lifting of the brushes from the sliding track. In addition, interruptions may occur due to friction-induced internal oscillations that occur at different rotational speeds.